1. Field
This invention relates to food products. The invention envisages a method for producing sandwiches, particularly sandwiches which are toasted or otherwise heated prior to being consumed.
For the sake of avoiding repetition, the term "sandwich" will be used throughout this specification and the claims to include a food product comprising two or more layers of bread which are brought together with an edible filling of any suitable kind therebetween. The layers may take the form of separate slices of bread cut from a conventional loaf or a single such slice folded over on itself. However, the layers may also take any other suitable form. They may, for example, particularly but not necessarily exclusively in a commercial operation, be formed from pieces of bread dough which are made into a desired shape before they are baked so that, after baking, they do not need to be cut or further shaped (other than for the removal of crust) before being used to make the sandwich. One such desired shape may be that of a conventional slice of bread.
Furthermore, the term "bread" is used in a broad sense in this specification and claims. It is used essentially to imply that the product is pre-baked or otherwise cooked before it is used for carrying out the method of the present invention. It is intended to include in particular any suitable bread-like product which incorporates baked dough as an essential ingredient and which is used to make a sandwich according to the methods of the present invention.
2. State of the Art
There is, of course, a well-known technique for making toasted sandwiches. Commercially available devices are provided for the purpose. These devices conventionally comprise a pair of plates which are joined together by hinges or the like so that they can be pivoted to an operational position in which the working face of the first plate faces the working face of the second plate. In use, a sandwich is placed between the plates, in contact with the working faces. The plates are then heated and the sandwich is toasted by the heat which is transmitted through the working faces to the sandwich.
Conventional such devices work best when the thickness of the sandwich is somewhat greater than the gap between the working faces. The sandwich is thus squeezed between the working faces which improves the contact, and hence the efficiency of heat transfer, between the plates and the sandwich. However, there is clearly a practical limit as to how much the sandwich can be squeezed since excess squeezing will not only tend to eject the filling from the sandwich (especially if the filling comprises a substance such as cheese which melts when it is heated) but will also have a deleterious effect on the quality of the sandwich.
The working faces of most conventional devices of this kind are flat. However, cavities or recesses are molded into the working faces of some such devices. The bulk of a sandwich is accommodated in a cavity of this kind, the edges of the sandwich overlapping the periphery of the cavity. The edges of the sandwich are thus squeezed between the portions of the working surfaces bordering the cavity and, when the toasted sandwich is removed from the edge, the edges are often found to be sealed together. This sealing is, however, achieved by the applied heat. This can be demonstrated by separating the plates before the heat is applied. It is then found that the squeezed edges are not fused together and easily become separated especially if an attempt is made to heat the sandwich without returning it to the aforementioned toasting device. Any liquid in the filling will run out if the sandwich is turned on its edge.
Bread toasting appliances wherein a slice of bread is positioned vertically on an edge in the appliance for toasting are in common use but are not generally used for heating sandwiches because the sandwich filling generally falls out of the sandwich when placed in a vertical position.
The applicant believes that there is a need for a sandwich product which can be supplied to users ready to be toasted or cooked in some manner, such as by microwave, a conventional oven, frying pan or grill, or common toasting appliance. However, if such a product is to be acceptable, it is essential that it must be capable of being handled during manufacture, packaging, transport, unpackaging, and cooking without falling apart. It must further be such that cheese, sauce, or any other substance in the filling should not be able to escape when it melts or becomes less viscous upon being heated. This is important to prevent the cheese, sauce, or other substances in the filling from running out of the sandwich product into an oven, pan, or toaster during heating of the product, particularly when heating is accomplished by positioning the sandwich product substantially vertically on an edge in a common toaster appliance. Most of such toasters are of the radiant heat type which reduces the time required to brown the outside and to heat the ingredients to about 1.5 to 3 minutes.
In an earlier attempt to provide an acceptable sandwich product, the inventor of the present invention has proposed to glue together the two slices of bread in a sandwich, using an edible glue. These proposals are set out in international patent application Serial No. PCT/NZ93/00104.
One drawback of gluing the slices together is that, although the layers are bonded together at lower temperatures, any meltable ingredients of the filling are still able to escape when they melt or becomes less viscous upon being heated. This limits the choice of ingredients.